Interconnects include cables, both electrical and optical, used to connect test systems to systems under test. Often, a test system is calibrated for a particular interconnect or family of interconnects. As a result, manual calibration can be required if the test system is used with interconnects other than those for which the test system is calibrated.
The quality of calibration of a test system to an interconnect can be measured using an eye diagram, which can be generated using an oscilloscope. An oscilloscope is a type of electronic test instrument that allows observation of constantly varying signal voltages. For example, an oscilloscope can present a two-dimensional plot of one or more signals as a function of time. Oscilloscopes can be used in communications test systems to display an eye diagram of a digital signal output from a receiver. The digital signal is repetitively sampled and applied to a vertical input of the oscilloscope and the data rate triggers the horizontal sweep, resulting in a superposition of many possible realizations of the signal viewed on top of each other. A user of a communications test system can use the eye diagram to evaluate the combined effects of noise and interference on the signal.
The user can also calibrate the receiver to a particular interconnect by adjusting the receiver and observing the effects of adjustments on the eye diagram. The user changes one parameter value, looks at the eye, then changes another parameter value, and so on. The user may have to test a hundred or more different configurations. Calibrating a receiver in this manner can result in an optimal setting but takes a long time and requires an oscilloscope and a certain amount of skill on the part of the user.
In light of these difficulties, there exists a need for methods, systems, and computer readable media for adaptive calibration of test systems for different interconnects.